The invention relates to devices for cooling the engine of a motor vehicle with combustion-engine or hybrid propulsion comprising an internal combustion engine.
More particularly, the invention relates to the cooling of the engine compartment overall.
In general, motor vehicles are equipped with an engine compartment incorporating an internal combustion engine closed off by a lower fairing, a heat exchanger, such as a radiator, through which a coolant passes and a fan placed upstream of the heat exchanger in order to blow air toward the engine and thus cool the internal combustion engine when the vehicle is in operation.
Any component able to close off the lower part of the engine compartment, which is generally open, in order to improve the aerodynamics of the vehicle is referred to as a “lower fairing”.
However, such a system allows only the front of the combustion engine to be cooled, and the cooled air has difficulty reaching the rear part of the engine, which means that some components of the engine are not sufficiently cooled and may be damaged by the heat.
In addition, when the internal combustion engine is stopped or running at low idle, the components in the engine compartment, and notably those on top of the engine, are subjected to a phenomenon of natural convection. What happens is that when the vehicle is no longer moving along, air situated in the confined region of the engine compartment is heated up to a large extent so that the components are subjected to high thermal stresses and may become damaged by the heat.
Reference may be made to document US 2010/0181050 which describes a vehicle comprising two fans which are intended to cool the front of a combustion engine via a heat exchanger. A first fan is powered by an electric motor and emits air through a heat exchanger. The air emitted by the first fan is recovered to drive a second fan able to convert the mechanical energy into electrical energy and to recharge an electric battery.
However, such a system is difficult to install because the combination of two fans leads to a significant bulk. In addition, such a system is unable to cool all of the components situated in the engine compartment once the vehicle is stopped.
Reference may also be made to document US 2010/0244445 which describes a turbine designed to turn a fan, of substantially horizontal axis, intended to cool the front of a combustion engine via a heat exchanger and to convert the work supplied by the fan turned by the flow of air coming from the outside into electrical energy and recharge an electric battery.
Such a system requires the combination of a turbine and of a fan in order to recharge an electric battery and is likewise unable to cool all of the components situated in the engine compartment once the vehicle is stopped.